1. Field of Invention
The invention relates to an ankle brace and footwear containing such a brace that restricts side motion of an ankle while allowing less restricted control of forward and rearward ankle motion.
2. Description of Related Art
The ankle joint is capable of two types of pivotal movement of the ankle bone (talus) about the leg bone. This first is dorsiflexion and plantarflexion movement (forward/rearward). The second is inversion or eversion (side-to-side). Various combinations of these permit full movement of the ankle. However, excessive movements, particularly in inversion, can cause ankle sprain.
Ankle braces are known that assist or restrict certain movements of an ankle. Such devices have included standalone orthotic devices and orthotic devices incorporated into footwear. However, many such devices are overly restrictive and useful for rehabilitation purposes only, as normal or athletic movements cannot be attained. Others while allowing more mobility are overly bulky, uncomfortable, and difficult to mount on or wear with shoes.
There is a need for a simple, yet effective ankle brace that can restrict side-to-side motion of an ankle while allowing a large amount of forward and rearward movement.
There also is a need for an ankle brace having a blade element that freely flexes about a fixed axis to follow forward and rearward movement of an ankle while restricting rotation transverse to this axis.
The present invention overcomes various problems of the art and provides an ankle brace comprising: a semi-rigid orthotic plate shaped to receive a wearer""s ankle or foot thereon, the orthotic plate having an upwardly extending rear support portion; at least one axial slip support bracket having an opening therethrough fixedly provided on the rear support portion; and a longitudinally extending blade element slidably attachable to the at least one axial slip support bracket at a proximal end thereof and substantially fixed relative to a leg of the wearer by at least one fixed support member at a distal end thereof. The blade element has an axial length, a thickness T extending in a fore/aft direction of the orthotic plate corresponding to a fore/aft direction of a wearer""s foot, and a width W. The ratio of T to W is selected so that the distal end is free to flex about the proximal end in the fore/aft direction and the blade element is substantially constrained from flexure in the width direction. A clearance between the blade element and the opening of the at least one axial slip support bracket is chosen so that slide movement of the blade element through the opening along the longitudinal axis is allowed but lateral movement in the width direction is constrained.
The present invention also provides a shoe having an integrated ankle brace, comprising: a semi-rigid orthotic plate shaped to receive a wearer""s ankle or foot thereon, the orthotic plate having an upwardly extending rear support portion; a shoe upper affixed to the orthotic plate; a sole portion located beneath the shoe upper; a heel portion located beneath the orthotic plate; at least one axial slip support bracket having an opening therethrough fixedly provided on the rear support portion; and a longitudinally extending blade element slidably attachable to the at least one axial slip support bracket at a proximal end thereof and substantially fixed relative to a leg of the wearer by at least one fixed support member at a distal end thereof. The blade element has an axial length, a thickness T extending in a fore/aft direction of the orthotic plate corresponding to a fore/aft direction of a wearer""s foot, and a width W. The ratio of T to W is selected so that the distal end is free to flex about the proximal end in the fore/aft direction and the blade element is substantially constrained from flexure in the width direction. A clearance between the blade element and the opening of the at least one axial slip support bracket is chosen so that slide movement of the blade element through the opening along the longitudinal axis is allowed but lateral movement in the width direction is constrained.